Abstract
In Mediterranean countries seawater might become a resource for the concrete production for sustainable construction industry. Nowadays its use, since it might induce the corrosion on ordinary carbon steel bars, is prohibited for the realization of reinforced concrete structures. Within the SeaCon Project, the use of seawater as mixing water has been studied in combination with corrosion-resistant reinforcement. This paper, firstly, discusses the influence of chlorides present in the seawater on the concrete properties related to the durability. Afterwards, the corrosion resistance of austenitic (304L and XM-28) and duplex (23-04 and 22-05) stainless steels reinforcing bars, and for comparison of carbon steel, embedded in alkaline and carbonated concretes made with seawater and subjected to different environmental conditions is evaluated. Results showed that seawater accelerated the early strength of concrete, whilst the carbonation penetration, the capillary suction and water absorption were slightly affected. Corrosion tests showed that corrosion did not initiate on 304L, 23-04 and 22-05 stainless steel bars, despite the presence of chlorides since the beginning even in the most aggressive exposure conditions and when concrete was carbonated; XM-28 reinforcement showed a slight change in corrosion behaviour in carbonated concrete exposed to the harshest conditions.
Highlights
One of the resources of the Mediterranean countries, as well as of other country all over the word is, undoubtedly, seawater, which is the largest water resource on the earth, which accounts for 97% of the available total water
The results showed that seawater accelerated slightly the early strength in comparison to the reference concrete, whilst similar strengths were obtained after longer curing time (360 days seem to be an exception)
It was observed that seawater accelerated the early strength of concrete cured in moist conditions, the strength after longer curing slightly decreased in comparison to the mix made with freshwater
Summary
One of the resources of the Mediterranean countries, as well as of other country all over the word is, undoubtedly, seawater, which is the largest water resource on the earth, which accounts for 97% of the available total water. Despite the clear potential advantages in terms of sustainability, the use of seawater or other chloridecontaminated materials, is currently forbidden in reinforced concrete by Standards, as indicated, for instance, by EN 206: 2016 which limits the total chloride-ion content in reinforced concrete to 0.2-0.4% by mass of cement [2]. This is mainly due to the associated risks of early corrosion of ordinary carbon steel bars [3] and to a possible influence on the concrete properties [4]. Both concretes have been characterized in terms of mechanical properties, carbonation resistance, capillary suction and water absorption
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
